Reciprocal actuator



May 11, 1948. OCHTMAN 2,441,505

RECIPROCAL ACTUATOR Filed July 1, 1946 2 Sheets-Sheet 1 a 2 INVENTOR mum/w UL'HTMHN ATTORNEY Patented May 11, 1948 UNITED STATES PATENT OFFICE.

RECIPBOCAL ACTUATOR Leonard Ochtman, Ridgewood, N. 1., anlgnor to Bendix Aviation Corporation, Teterboro. N. 1., a corporation of Delaware Application July 1, 1946, Serial No. 880,806

8 Claims. (Cl. 192-142) This invention relates to actuators, and particularly to means for regulating the strokes of reciprocable actuator elements;

An example of an actuator for which the invention is adapted and which is illustrated herein, is one for operating a. member, such as a tab, a flap or other element of an airplane.

In connection with such application, it is important, in certain cases, that the actuated memberbe positioned and stopped with precision in any position to which it may be moved, and also important, as improved by the invention hereof, that the limiting movements of the actuator be adjustable and precisely effected in very short distances.

It is also important that such actuators should be as light in weight, and occupy as little space as possible, consistent with effective operation and other factors.-

An object of the invention is to provide novel light weight compact means of few parts for adjusting the movement or strokes of a reciprocable actuator element.

Another object is to provide novel means which is adjustable laterally of or across the path of movement ofan element for regulatin the extent of movement of the element along the path. 1

Another object is to provide novel means whereby such laterally movable means eifects its adjustment of the element along the path in line or micrometric steps, and is movable bodily along the path to efiect the adjustment in major steps.

Another object is to provide novel means for effectively mounting such laterally movable means in permanently mounted adjusted position by friction, whereby the adjustments may be effected without removing or releasing any parts, and without replacing or tightening them.

Another object is to provide novel cushion stop means for, and in novel combination with, a reciprocatory actuator and other elements, whereby the actuator element is effectively stopped at the ends of its maximum strokes within limits commensurate with the precision timing and stopping characteristics above set forth, and whereby the size and weight of the combination are reduced.

Another object is to provide means of the above-indicated character that is simple and durable in construction, economical to manufacture, and efiective in its operation.

These and other objects and features of the invention are pointed out in the following description in terms of the embodiment thereof 2 which is shown in the accompanying drawings. It is to be understood, however, that the drawings are for the purpose of illustration only, and are not designed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings:

Figure 1 is a view, on an enlarged scale, partially-in side elevation and partially in section of an actuator of one form embodying the invention:

Figure 2 is a view, taken substantially along the line 22 of Figure 1 showing a member thereof in diiferent positions indicated by full and broken lines, respectively; and

Figure 3 is a view similar to a portion of Figure 1, showing a modification of the invention.

Referring to Figure 1, the device shown comprises, in general, a gear housing [0 having portions l2 and I4 for enclosing a gear train [8, a housing portion ll enclosing limit switches 20 and 22 and means 24, for attachment to a member to be actuated, a housing portion 28 enclosing a driving disc 28, and clutch disc and brake means 20 and 32, respectively, 'a housing portion 34 enclosing electromagnetic means 38, and a housing portion 38 comprising parts 40 and 42 enclosing a reversible motor H. The housing portions l2, [4,18, 28, 84, 40 and 42 are connected to each other as by screws, dowel pins and the like.

The device, as a whole, isadaptedto be mounted on a base, as by bolts 48 and 50 extending through the housing portions I4 and I8,

respectively, and connected to an element to be actuated, as by an eye 52 on the means 24.

The means 24 comprises a shaft 54 having a short length 58 journaled, as by ball bearings .58 and 88 in the gear housing portion l4, and a long screw length 82 protruding from the gear housing l0.

The gear train 18 includes an output gear 64 on the short length 58 of the shaft 54, and an input gear or pinion i8 fixed to a short driven shaft 88, which is iournaled in ball bearings III in the housing 28. I

The clutch disc 30 is splined to the driven shaft 88 for rotation therewith and axial movement relative thereto, and is biased to the right, as shown, toward a lock ring 12 in a groove of the shaft 88, by a spring 14 around the'shaft 88 pressing oppositely with a given force between the clutch disc and the inner race of one of the ball bearings II.

The perimeter of the brake I2 is of axial substantially L-section one portion I of which, having the braking surface, is of larger inside diameter than the outer diameter of the driving disc 28 and normally, in the inactive positions of the parts illustrated, surrounds the disc 28 in engagement with the clutch disc 30 under the pressure of springs 16 having greater force than the force of the clutch spring I4. The springs I6, of which in this instance there are four, are spaced about the disc axis, and mounted around pins I8 which are screw threaded or pressed in place inthe'brake 32.

The driving disc 28 is keyed to an armature shart 82 of the motor 44, and fixed to the shaft, as by a nut 84. The shaft 82 is journaled in an anti-friction bearing 86, which is mounted in a partition 88 having a perimetral portion 80 clamped between the housing portions I4 and 34.

The electromagnetic means 38 comprises a pair of laminated cores 82 of axial substantially E- shape, only one of which shows, and which are in register with each other at opposite sides of the driving or motor shaft 82. A coil winding 84 linlts the middle legs of the cores 92 around the shaft 82 spaced from the latter, which coil 94 is connected to the motor 44 for simultaneous energization and deenergization therewith.

Laminated armatures ilti, disposed opposite the pole ends of the core legs, are carried by a diamagnetic plate 90. The plate is mounted on pins I00 which are disposed in tubular spacers IN and with the latter are slidably extended through the partition Bit and fixed to the brake 32.

Movement of the armatures 96, to the left as viewed in Figure l, is effected by the springs I6 and limited by engagement of the plate 98 with the partition 88.

Movement of the armatures 96, to the right, is effected when the coil 94 is energized, and limited, by engagement of the brake 32 with the partition 88, to provide a slight air gap between each armature 88 and the corresponding core 92.

The clutch disc 30 is of substantially the same diameter as the brake 32, and has a friction facing ring or band I02 of radial extent between its inner and outer edges sufiicient to alternately engage the brake 32 and the driving disc 28.

The means 24 further comprises an elongated actuator member or element i04 carrying the eye 52, at one end, and having, at its other end, a short length constituting a nut I08 on the screw shaft In this instance, the screw threads of the nut and the shaft have rounded troughs, in which bearing balls are disposed to provide antiiriction drive of the nut I00 by the shaft 54.

The actuator element I04 is of tubular form longitudinally slidably mounted in a bushing I08 supported in the outer end of the switch housing IS. The switches 20 and 22, which are in circuit with the motor 44, have push buttons IIO and I I2, respectively, which must be held in the inner or pushed positions thereof to maintain the switch contact members in open circuit condition, and which close the circuit when released.

The switches 20 and 22 are mounted on a bracket I I4 secured to the housing I8, as by bolts HE. A switch operating member I'I8, secured to the bracket II4 as by rivets or screws I20, has operating arms I 22 and I24 for the switches 20 and 22, respectively, and which arms slope divergently of each other from the bracket I I4 along and toward the actuator element I04 to end portions or loops I26 disposed one on each arm for pushing the buttons '0 and H2.

Referring also to Figure 2, split sleeves or collars I28 and I30, clamped to the actuator element I04, as by bolts I32, are disposed around the element I04 in concentric relation to the axis of the element and of the screw shaft 62.

Each collar I28 and I30 has a fixed radial outer shoulder I34, and a removable radial outer shoulder in the form of a split lock ring I36 disposed in a radial outer groove of the collar. In this instance, a washer I38 is disposed around each collar to cover the split in the ring I36, and to thereby prevent any possible interference by the lock ring, by reason of its split, with rotative adjustment of switch arm operating members I40 and 1142 disposed around the collars I28 and I30, respectively. The washer I88, which is of advantage in certain applications, may be omitted in other cases, as desired.

Each member I40 and I42 has an outer perimeter I44 eccentric to the axis of the corresponding collar, and including means, such as recesses I45, providing for adjusting the member about the element I04 and the corresponding collar, as by the use of a spanner wrench or other tool.

Friction spring means I48, which in this instance is of annular wave-like form, surrounds each collar H8 and I30 and is compressed axially between the corresponding shoulder I34 and the corresponding member I40 and I42 for maintaining the latter in adjusted position.

To adjust the length of the strokes of the ac tuator element I04, the collars I28 and I30 are moved axially along the element to effect major steps of such adjustment, and set in adjusted position by manipulating the bolts I32,

To effect fine or micrometric steps of such adjustment, along the axis of the actuator ele ment I04, each arm operating member I40 and I42 is moved about such axis against the action of the spring I48, which not only yields for such adjustment, but also sets the member I40 or I42 in adjusted position, without requiring the removal or release of any element.

Figure 2 indicates the member I40, by a dotand-dash line and a full line, respectively, in different positions to which it may be adjusted.

The latter adjustment, by reason of the eccentricity of the perimeter I44, particularly as viewed in Figure 2, raises or lowers a point B on such perimeter, which engages the corresponding switch arm IE2 or lit to any position in a distance A, thereby shortening or lengthening the axial distance which. the eccentric member I40 or 1142 must travel to actuate the C01lS130l1Ciing switch or Thus, the member I40 is adjusted laterally of the axis of the element I04 to raise or lower the point B to affect the longitudinal or axial movement of the element I04.

Cup-lil e members I50 constituting stationary stops fitted in recesses in the housing portions I4 and I8, respectively, support belleville springs I52, which are held in position by lock rings I54 disposed in grooves in the members I50, for engagement with stop end portions I56 of the collars I28 and I30, respectively. The springs I52, which-are of sheet metal, and of frustoconical washer-like shape, have characteristics effective against high loads in short range of axial deflection, and non-linear deflection, which does not vary appreciably over a substantial critical portion of such range. These characteristics render the springs exceptionally effective in the combination hereof for quick short range cushion stop action. The springs conserve space and weight by comparison to coil springs or other cushioning means, which would be ineffective in the places of the springs I62 hereof.

Although the springs I52 may be employed singly or of various numbers in series in each of the members I50, one is employed in each member I50, in this instance.

In operation, with the parts positioned as they are when the motor 44 and the coil 94 are deenergized, as illustrated, the left hand switch 20 is open, but the right hand switch 22 is closed to condition the circuit such that, when a main operating switch, not shown, is thrown, in one direction, to close the circuit of closed switch 22, the motor 44 actuates its shaft 82 to rotate in the proper direction for causing the screw shaft 82 to move the actuator-element I04 to the right. The latter movement immediately causes the arm operating member I40 to release its arm I22 to close the switch 20,'but the circuit of the latter switch is maintained open by reason of the fact that the main operating switch has been moved in the above-mentioned direction closing the circuit of the switch 22.

When the arm operating members I40 and I42 are thus both out of contact with and between the switches 20 and 22, at any desired position, the latter switches are both closed, such that, by opening the main switch to open the circuit of the switch 22, the actuator element I04 will be stopped in such position. Thereafter, the main switch may be again closed in the above-mentioned direction to close the circuit of the switch 22 and continue movement of the element I04 to the right, or the main switch may be closed in the opposite direction to close the circuit of the switch 20 and cause movement of the element I04 to the left.

Also, with the parts positioned as they are when the motor 44 and the coil 94 are deenergized, the springs I6 prevail over the spring I4 to engage the brake 32 to the clutch disc 30, whereby the pinion 66 and the mechanism'at the output side of the pinion are prevented from being moved.

When the motor 44 and the coil 94 are next energized, the armatures 96 are at first attracted to the cores 92 against a force equal only to the difference between the force of the springs 16 and the spring I4, this reduced pull being at a time when the armatures 96 are farthest from the cores 92 and continuing until the clutch disc 30 engages the driving disc 28.

Upon this action, when the armatures 96 are closer to the cores 92 in a stronger flux field, the brake 32 is more readily pulled free from the clutch disc 30 against the full force of the springs 16. With the driven shaft 68 thus con- I nected to. the driving or motor shaft 82, the motion is transmitted through the pinion 66,

the gear train I6 and the gear 64 to the screw shaft 62 to cause the actuator element I04 to move axially, as aforesaid.

If the element I04 is allowed to travel its full working stroke to the right, the switch 22 is actuated by the arm operating member I42 to deenergize the motor 44 and the coil 94, whereupon the brake 32 is instantaneously released and is moved by the springs I6 into contact with the clutch disc 30, applying a braking effect and simultaneously moving the clutch disc out of contact with the driving disc 28 against the force of the spring 14.

the nut, and render it easier to reverse rotation of the shaft.

Referring to Figure 3, in which corresponding parts are designated by corresponding reference numerals, the construction and operation are similar to those above set forth, with the exception that a spring I58, of construction and characteristics similar to those of the springs I52 above set forth, is carried by each of collars I60 and I62 for cooperation with stationary stops I64 and I66, respectively.

The collars I60 and I62 have radial outer fixed shoulders I68 against which the springs I58 are held, as by lock rings I10, and although the springs may be employed singly, as shown in Figure 1, or of various numbers in series, two are employed in the structure of Figure 3, nested one within the other, to increase the resistance of one spring in the given radial and axial space [for the desired effect in this instance.

Although only two embodiments of the invention have been illustrated and described, various changes in the form and relative arrangements of the parts may be made to suit requirements.

What is claimed is: I 1. In an actuator comprising a reciprocable element, and means including electro-responsive means for operating said element, the combination of switch means in circuit with said electro-responsive means supported laterally of said element, switch operating arm means sloping along and toward said element, and means carried by the element adapted for adjustment therealong including a split collar around I and adjustable in major steps along said element, means for clamping said collar to the element in adjusted position, said collar having a radial outer shoulder and a radial outer groove spaced axially from each other, a lock ring in said groove protruding therefrom, an arm operating member,

surrounding said collar between said lock ring and said shoulder having an arm engaging outer perimeter eccentric to the collar axis and having means supported laterally of the path of movement of the element, the combination of switch operating means carried by the element and adapted for adjustment relative to the element along said path, said switch operating means including a member having an outer perimetral portion movable laterally of said element in effecting said adjustment, means for holding said member in adjusted position, stop means movable with said element, stationary stop means cooperating with said movable stop means, and spring means of short axial range of movement This action occurs also when the motor 44 and (I and high load characteristics for cushioning the impact between said movable stop means and the stationary stop means.

3. In a device comprising a reciprocable element, and means for operating said element, the combination of switch means disposed laterally of the path of movement of said element, and switch operating means carried by the element adapted for adjustment relative to the element along said path including a collar around and movable along said element in effecting major steps of said adjustment, means for holding said collar in adjusted position, said collar having fixed and removable radial outer shoulder means spaced axially from each other, a switch operating member surrounding said collar between said shoulder means having a switch engaging outer perimeter eccentric to the collar axis and movable about the collar \for effecting fine steps of said adjustment, and means for holding said switch operating member in adjusted position.

4. In a device comprising a longitudinally movable shaft-like element, and means laterally adjacent thereto, the combination of an axially split collar adapted to be concentrically clamped about said element in axially adjusted position thereon, said collar having a radial outer shoulder and a radial outer groove spaced axially from each other, a lock ring in said groove protruding therefrom, a member surrounding said collar between said lock ring and said shoulder having an outer perimeter eccentric to the axis of said collar and said element and adapted for adjustment about said axis for axially engaging said laterally adjacent means for actuation of the latter by said element, and friction spring means of annular wave-like form around said collar between said shoulder and said member, against the action of which spring means said adjustment is effected.

5. In a device comprising a movable element, and means responsive to movement of the element, the combination of actuating means for said responsive means carried by said element and providing for adjustment of the extent of said movement, said actuating means including a member movable relative to the element in the direction of said movement in effecting major steps of said adjustment, means for holding said member in adjusted position, a second member on said first member movable relative thereto laterally of said movement in effecting fine steps of said adjustment, and means forholding said second member in adjusted position,

6. In a device comprising a longitudinally movable shaft-like element, and means laterally adjacent thereto, the combination of a collar adapted to be concentrically held in position about said element in axially adjusted position thereon, said collar having fixed and removable radial outer shoulders, respectively, spaced axially from each other, a member surrounding said collar between said shoulders having an outer perimeter eccentric to the axis or said collar and said element and adapted for adjustment about said axis for axially engaging said laterally adjacent means for actuation of the latter by said element, and friction spring means around said collar between said member and one of said shoulders, against the action of which spring means said adjustment is effected.

7. In a device comprising a movable element, and means responsive to movement of the ele-- ment, the combination of means adapted to be carried by the element for actuating said responsive means and providing for adjustment of the extent of said movement for actuating said responsive means, said actuating means including a member movable relative to the element in its direction of movement in efiecting major steps of said adjustment, means for holding said member in adjusted position, a second member surrounding said first member having an outer perimetral portion eccentric to the axis thereof movable about said axis in effecting fine steps of said adjustment, and means for holding said second member in adjusted position.

8. In a device comprising a movable element, and means responsive to movement of the element, the combination of means adapted to be carried by the element for actuating said responsive means and providing for adjustment of the extent of said movement for actuating said responsive means, said actuating means including a member surrounding said element having an outer perimetrai portion eccentric to the axis of movement thereof movable about said axis in effecting said adjustment, and means for holding said member in adjusted position.

LEONARD OCH'I'MAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,509,685 Moore Sept. 23, 1924 2,247,562 Santen July 1, 1941 2,375,422 Leland Sept. 8, 1945 2,383,901 Werner Aug. 28, 1945 2,411,101 Millns Nov. 12, 1946 2,417,434 Mead Mar. 18, 1947 

